1. Field of the Invention
The present invention relates to a digital data recording method for recording digital data on a recording medium and to a digital data recording medium for saving digital data.
2. Description of Related Art
One of apparatuses for recording and playing back digital data on recording mediums is known as a streaming tape drive. Such streaming tape drives having recording capacities as having recording capacities as large as hundreds of megabytes, although their actual capacity depends on the length of a magnetic tape used as a recording medium. Further such tapes drives are commonly used for backup storage of bulk data which has been saved on a mass recording medium such as a hard disk in a computer. The streaming tape drive is also used for saving image data which is often huge in quantity.
The streaming tape drive is provided with a rotary head operating in a helical scanning mode to record and play back a data on a magnetic tape of the 8-mm VTR format. An example of a conventional streaming tape drives is disclosed in PCT Application No. PCT/JP96/02345 (filed on Aug. 22, 1996) as invented by the same applicant.
The streaming data drive employing a magnetic tape of the 8-mm VTR format as a recording medium includes an input/output interface such as a small computer system interface (SCSI) for data to be recorded or played back.
In recording, data supplied, e.g. from a host computer, is introduced via the SCSI interface to the streaming tape drive. The data may be carried in units of a fixed length data groups and if necessary, compressed by a known data compression method and temporarily saved in a buffer memory. The data released from the buffer memory is then supplied in units of a predetermined data length termed a "group" to a record/playback system where it is recorded on a magnetic tape with a rotary head.
In playback, the data saved on the magnetic recording tape is read out by the rotary head and also saved temporarily in a buffer memory. The data is released from the memory buffer and, when having been compressed in the recording, expanded by a known expansion method before being transferred via the SCSI interface to a host computer.
It is desired that the storage efficiency streaming tape drives or mass data record/playback apparatus be improved in order to allow for the recording of greater amounts of data on a given recording medium. It is also essential that the data saved on the medium is accessed and read at as a great a speed as possible.